3 hours? Wow. Well, maybe that involves setting up the fuelling but I still can't see it taking much more than half that for a professional mechanic, TBH....
I doubt you'll find any guides as such, but if you have the standard parts, you know what you're looking for!
The cans themselves are just a few nuts and bolts.
I've never done it but I imagine the ECU is with the other electrics under the 'tank' somewhere, and you'll have to remove the 'tank' to change the filter anyway.
Getting the tank off is fiddly, but not too hard really. Just remove every bolt you can see and go slowly, remembering what goes where. The air filter is in the airbox under there somewhere, and I'd imagine the ECU will be a couple of screws and a plug to change, once you've found it. It will look like the one you have already! And the plug will only plug into one place, so you can't go wrong.
Do you have a mate that's mechanically minded?
If not try asking on here, someone will be able to guide you through it better than me.